Greetings
A 1912 razor is a very good place to start SE shaving if for no other reason than as Paul says that it is the razor that everybody uses as a yardstick to compare others against. I do not know the true statistics but I suspect that nearly as many 1912's were made as all the other models put together, it's a model that ran and ran for years.
Don't worry about what sub model it is (they were made both sides of the Atlantic and badged up under different names) but they are all quite similar when you first start SE shaving. I suggest you just buy a cheap one, they are all brass underneath the plating in any case and a bit of bare brass won't effect the shave!
Regards
Dick.